For questions regarding the visual system, which serves to transduce light energy into neural impulses, or regarding visual perception, how we interpret such incoming visual information.

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7
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1answer
62 views

What are biologically plausible ways to model binocular disparity?

I figure there is a vast body of literature on stereovision, both neurophysiological and computational studies. Computer Vision also provides some algorithmic insight on implementing binocular ...
7
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1answer
140 views

How to set up a binocular rivalry experiment which splits a single image in two separately controlled ones?

The question is about the actual physical setup and steps needed to take in order to experiment with the phenomena. I found a tutorial on jove.com, "How to Create and Use Binocular Rivalry", and it ...
7
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2answers
142 views

Are there physical techniques to relieve eye strain? [closed]

I asked a question about eye strain Does looking into a mirror relieve eye strain in a similar way to looking at distant objects?. Are there any physical exercises or techniques that can help to ...
6
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2answers
250 views

Are closed eye movements related to the content of dreams or the imagination?

During rem sleep there are observed eye movements, which seem like they would correlate with the person visualizing their dreams. Do their eye movements actually try to follow what they're dreaming ...
6
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2answers
80 views

Do the colour blind have a distinct visual cortex structure?

Studying the structure of the visual cortex, it seems there are many neural structures specifically dedicated to detecting and interpreting colour. For example, parvocellular cells are particularly ...
6
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1answer
107 views

Visual acuity and offset stimuli

I'm currently setting up and experiment that utilises a visual search task that contains a circular array of target letters and a distractor that falls outside the circle. Obviously the further away ...
6
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2answers
150 views

What is the difference between spike-triggered averaging and reverse correlation?

I'm interested in the difference between spike-triggered averaging and reverse correlation. In some papers (i.e., Schwartz, Odelia, et al) I see the term 'Spike Triggered Averaging'. In others, (ie ...
6
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1answer
80 views

Any research on how we use visual category information in visuomotor tasks?

So I've been reading up on the Two-streams Hypothesis*, and it bothers me that the explanations both sides give only extend to tasks involving one type of visual information. For example, an ...
6
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1answer
75 views

In psychophysics, why are log luminance rather than absolute luminance values reported?

Are there any papers which justify converting into log luminance? For example papers showing humans being sensitive to changes in log luminance rather than luminance per se?
6
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1answer
80 views

Relationship between oculometry/pupillometry and disorders of consciousness

I recently got to wondering whether certain eye movements or pupillary responses were correlated with disorders of consciousness (coma, VS, MCS, or even locked-in syndrome). I know that the pupillary ...
6
votes
1answer
277 views

Does the structure of consciousness mimic that of the visual process?

It seems to me that the structure of the conscious mind has some strong similarities to the way our visual field functions. The visual field has a strong and detailed focus at the center, and this is ...
6
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1answer
171 views

How is light processed by the human brain when awake and in dreams?

I've recently seen this great video: How your brain tells you where you are. The video discusses how certain cells within the brain fire based on proximity to objects. There are great examples of ...
6
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1answer
306 views

How much red/orange is needed to stimulate hunger?

A common claim thrown around is that red and orange are great for restaurants because it stimulates hunger. However, I've heard time and time again that this does not work in web design because you ...
6
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2answers
284 views

How are humans able to read scrambled text/characters (e.g., CAPTCHA)?

So I'm doing a research on developing a new text-based CAPTCHA system. I've devised a scheme where characters in a text are broken/split individually and randomly, making it difficult for OCR machines ...
6
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1answer
70 views

How long does it take to learn to cane travel?

How long does it take the average person (either sighted or blind) to learn to use the guide cane successfully for mobility purposes? Source: Lions. Because required training times will depend on ...
6
votes
1answer
273 views

Are there gender differences in color discrimination ability?

There appears to be a prevalent stereotype that girls seem to have "heightened" color perception. By this term, I mean that they can identify the salient features of different shades of color. However,...
6
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0answers
140 views

Has there been a neuroscientific explanation of the color phi phenomenon?

The color phi phenomenon is a perceptual illusion in the visual domain which was demonstrated in an experiment by Kolers and von Grunau (1976). The experiment is as follows. A sequence of coloured (...
6
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0answers
47 views

Source for turning cone cell opponent process diagram into equations

There is a diagram on wikipedia that is part of the article on the opponent process. I assume practical equations have been developed, at least reasonable approximations, but they appear to be missing ...
5
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2answers
1k views

Where is the visual “image” that we “see” finally assembled?

David Hubel's online book, Eye, Brain and Vision describes in great detail our early visual system. The image that we are conscious of when we open our eyes goes through a complex path: The final ...
5
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3answers
141 views

Are there any cognitive models for visual navigation?

I've seen a few neuroscience accounts of visual navigation and many A.I. projects, but no psychologically plausible accounts that actually solve the computational problem (i.e. produce a working model)...
5
votes
1answer
864 views

How does the brain read rotated text?

Suppose a human ran across a letter written at a 45 degree angle. How does the brain read this text? Most people don't often see text written at an angle, so it seems safe to assume that the brain ...
5
votes
2answers
159 views

Sensitivity of human eye to luminance

I heard once that the human eye has a logarithmic scale for luminance, e.g. to "feel" that a surface is three times as luminous compared to another, the former emits a light 8 times more powerful than ...
5
votes
2answers
439 views

Minimum duration for presenting a visual stimulus on screen

My experiment involves presenting simple visual stimuli briefly on screen (200 ms to 1000 ms). The stimuli would be simple enough (e.g. a circle and a line) but I want to use a range of durations to ...
5
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2answers
238 views

Is there a difference between visual short term memory and visual working memory?

As far as I can tell the two terms are used interchangeably. Do these two separate terms exist for historical reasons, or is there a distinction I'm missing?
5
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2answers
247 views

What is the minimum angle off horizontal before a line visually appears inclined at first glance?

Here is a straight line, which visually looks like a straight line: At first look (lets say minimum 2–3 sec.) the line below looks straight, but after some time you can see that it is actually an ...
5
votes
1answer
193 views

Distortion of faces presented serially in peripheral vision

I've kind of already answered this question for myself, but I can't resist sharing it anyway. Please feel welcome to add anything you can in another answer. Stare at the cross in the middle and try ...
5
votes
1answer
172 views

Why is my Gabor patch not resizing as a function of the bounding box?

I'm trying to create a Gabor patch of variable size for an upcoming experiment. Below is the python function used to generate the code. The code was ported from this tutorial for Matlab (assume <...
5
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2answers
81 views

Why vision cannot count things instantly?

If vision can instantly "see" 30x30 grid, why does the brain often need to count rows and columns for understand there is 30 rows and 30 columns? Why does the brain fail to instantly count?
5
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2answers
48 views

Do we have a predisposition to view visual stimuli in a clockwise pattern?

I understand that we typically view the center of the image first and then are likely to move on a horizontal axis, but is there evidence that we tend to follow a clockwise path when viewing more ...
5
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1answer
538 views

What is the brain power devoted to vision and haptics?

I heard a talk by Vincent Hayward on the sense of touch as a multi-modal system, where he claimed that the brain power devoted to haptics is at least as big as the one devoted to vision. I have found ...
5
votes
1answer
129 views

Perceptual flicker when rotating my face

Informal Experiment: I look up at a wooden beam on the ceiling, or I look at the office door; both the door and the ceiling are about 2 meters from my face. I rotate my face 90 degrees left or right ...
5
votes
1answer
51 views

What is the relationship between visual attention network and visual stream (Two-streams hypothesis)?

There are two visual attention networks proposed by Maurizio Corbetta and Gordon L. Shulman (2002). These are top-down and bottom-up attention networks. One system, which includes parts of the ...
5
votes
1answer
77 views

Binocular rivalry in animals?

Are there any experiments on binocular rivalry in animals? (In humans, brain responses to Rubin's vase are for example well studied.)
5
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2answers
135 views

Inducing Auditory-to-Visual Synesthesia

I recently watched an interesting video that was discussing conveying color to the blind through language. It implied that there may be a way to insert the sensation of color into a person's mind via ...
5
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1answer
47 views

Why can't hemineglect patients be trained to actively pay attention to their neglected side?

I'm still having a hard time understanding the symptoms of hemineglect, mainly because perception and attention has been two peas of a pod for most of my experiences. A Scholarpedia article states ...
5
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1answer
268 views

Computational model of biological object recognition

The human brain can achieve a remarkable ability to recognize visual patterns in an Invariant, selective and fast manner. The human visual system is quite powerful. It has an exquisite selectivity ...
5
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0answers
37 views

Is there a hierarchy of gestalt visual stimuli processing?

Let's say that we have a set of shapes. They can be grouped according to the different Gestalt laws of grouping. However, different Gestalt principles will divide the set into different groups, e.g. ...
4
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2answers
1k views

What does hemispatial neglect vision look like?

I need to know more about hemispatial neglect, in order to compose a picture of what it would look like to someone who has this issue. Is there any resources for finding more about their actual ...
4
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3answers
70 views

Is prior experience necessary to perceive the Kanizsa triangle illusion?

We know the Kanizsa Triangle. Kanizsa Triangle I was socialized in a "western" world, where I learned mathematics for about 13 years; I have designed products surrounding me using geometric forms ...
4
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1answer
83 views

Are we actually seeing black colored objects?

We know that black objects absorb light with almost all the frequencies of the visible spectrum. This means there will not be any frequency of light reflected and falling on our retina, in order for ...
4
votes
1answer
45 views

Does transparency have its own visual channel?

Referring to (for example) Visual Thinking for Design, the book discusses various low-level processing channels in the brain. Colour and orientation are two examples. I wonder if transparency is ...
4
votes
1answer
3k views

Why do humans' eyes enter an unfocused gaze when recalling a memory or imagining something?

The question is self-explanatory (I hope). Is this trait unique to humans? Does the direction of the unfocused gaze indicate anything about which physical part of the brain is being utilized? Is ...
4
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1answer
415 views

Does looking into a mirror relieve eye strain in a similar way to looking at distant objects?

Sometimes when having an eye exam the eye chart is viewed through a mirror to increase the distance between the person and the chart. When using consoles, it is recommended to look away from the ...
4
votes
3answers
113 views

Why is it easier to see black text on a white background?

I'm wondering why it's easier to see black text on a white background than it is to see white text on a black background. I say that it's harder based on life experience (Hate webpages with black ...
4
votes
1answer
59 views

Is there a difference between the time/effort it takes for the blind and the sighted to learn to read Braille?

The visually deprived brain undergoes extensive remodeling due to cross-modal plasticity. This leads to increased areas of the cortex being available for other purposes such as tactile processing. Now ...
4
votes
1answer
31 views

What study showed that humans can successfully detect objects within images once they are able to recognize those objects?

A professor in an online lecture I was watching referenced a study which he said showed that our ability as humans to detect objects within scenes (especially complex scenes) was very much connected ...
4
votes
1answer
67 views

What is the metabolic load of the visual system?

The brain consumes energy at eight times the rate that would be predicted from mass alone (20% of total organismic load). How much of this is drawn from the visual system? How does the metabolic load ...
4
votes
1answer
56 views

Asaccadia adaptation

Can asaccadia (i.e., lack of saccades, due to neuronal or muscular damage) be overcome? Do other muscles (e.g., neck) compensate? Are the resulting gaze patterns the same as for saccades, and are they ...
4
votes
1answer
123 views

Is there terminology for perceptual illusions at the moment that figure-ground reversal occurs?

I'm looking for a term in the perception / cognition area of research. I recently saw this visual illusion that 'flips' what is negative-space and what is positive-space. This is known in the arts ...
4
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1answer
229 views

Sensory dissonance: Will the visual or auditory channel win?

Is there any research showing that our visual channel takes precedence over the auditory channel (or vice versa) if there is some dissonance between them? Examples: Say a person driving a car ...